How effective are vaccines against Delta variant? Reports vary as immunized patient dies in Calgary hospital
As confirmed cases of the Delta variant of COVID-19 continue to rise in Alberta, there are conflicting statements regarding how effective the first dose of vaccine is at protecting against severe outcomes of infection.
Alberta Health Services confirms a patient in their 80s, who had received two doses of MRNA vaccine before contracting the Delta variant, died in an outbreak at the Foothills Medical Centre in Calgary. A second unvaccinated patient, who was also over the age of 80, also died in the outbreak.
The outbreak at the hospital in northwest Calgary now spans two units with confirmed cases in 21 patients and nine staff members.
In response to those outbreaks, AHS says vaccines were given to those in hospital at risk of exposure to the Delta variant — also known as B.1.617.2, that was first identified in India.
Earlier this month, AHS officials told CTV news a first dose of an MRNA vaccine such as Pfizer or Moderna offers 33 per cent protection against the Delta variant with a single dose and coverage increased to 88 per cent with a second dose.
Yet, on Monday, Premier Jason Kenney tweeted a report from the United Kingdom — where cases of the Delta variant are rising —indicating one dose of Pfizer vaccine is 94 per cent effective against hospitalizations involving the Delta variant and increases to 96 per cent after a second dose.
Alberta confirmed its first case of this variant of concern on April 8.
According to the latest data, it has spread to 356 confirmed cases, with more than 300 in the Calgary health zone.
University of Calgary biologist and member of the 'COVID-19 to Zero' advocacy group Gosia Gasperowicz says the exponential growth of this variant could potentially result in as many as 2,000 daily new cases in Alberta by early August.
CTVNews.ca Top Stories
![](https://www.ctvnews.ca/polopoly_fs/1.6859632.1713954182!/httpImage/image.jpg_gen/derivatives/landscape_800/image.jpg)
Half of Canadians have negative opinion of latest Liberal budget: poll
A new poll suggests the Liberals have not won over voters with their latest budget, though there is broad support for their plan to build millions of homes.
opinion Why you should protect your investments by naming a trusted contact person
Appointing a trusted person to help with financial obligations can give you peace of mind. In his personal finance column for CTVNews.ca, Christopher Liew outlines the key benefits of naming a confidant to take over your financial responsibilities, if the need ever arises.
Twins from Toronto were Canada's top two female finishers at this year's Boston Marathon
When identical twin sisters Kim and Michelle Krezonoski were invited to compete against some of the world’s most elite female runners at last week’s Boston Marathon, they were in disbelief.
Ottawa injects another $36M into vaccine injury compensation fund
The federal government has added $36.4 million to a program designed to support people who have been seriously injured or killed by vaccines since the end of 2020.
Senate expenses climbed to $7.2 million in 2023, up nearly 30%
Senators in Canada claimed $7.2 million in expenses in 2023, a nearly 30 per cent increase over the previous year.
NASA hears from Voyager 1, the most distant spacecraft from Earth, after months of quiet
NASA has finally heard back from Voyager 1 again in a way that makes sense. The most distant spacecraft from Earth hadn't sent home any understandable data since last November.
U.S. Senate passes bill forcing TikTok's parent company to sell or face ban, sends to Biden for signature
The Senate passed legislation Tuesday that would force TikTok's China-based parent company to sell the social media platform under the threat of a ban, a contentious move by U.S. lawmakers that's expected to face legal challenges.
Train derailed in Sarnia after colliding with a truck
Police are investigating after a transport truck collided with a train in Sarnia.
Photographer alleges he was forced to watch Megan Thee Stallion have sex and was unfairly fired
A photographer who worked for Megan Thee Stallion said in a lawsuit filed Tuesday that he was forced to watch her have sex, was unfairly fired soon after and was abused as her employee.